1. Field of the Invention
The present invention relates to phase shifters in general, and more particularly, to utilizing a means for shorting a slotline to vary the length of the slotline to a fraction of its predetermined length as measured from the open radiating end portion to the means for shorting to reflect electromagnetic energy, and more specifically, use a slotline spanned by selectively actuated electrostatic switches capable of reflecting electromagnetic energy when actuated into a closed position, thereby creating a slotline short for phase shifting.
2. Description of the Related Art
Electronically scanned phase shifting arrays have used semiconductors as the phase control elements. However, elements such as pin diodes, field effect transistors (FETs) or monolithic microwave integrated circuits (MMICs) consume undesirable amounts of power as antenna frequencies are increased. Phase shifting reflect arrays have previously been done with ferrites which are slow, have higher loss, and have high driver power consumption, as well as require integration with the antenna. The requirement for antenna integration results in increased cost to the overall system.
Changes in integrated circuits have been possible due to recent developments in microfabrication techniques. These changes have been addressed to making the devices smaller, more efficient, and capable of large scale production at low cost. More specifically, micromachining includes the techniques of planar technology, wet chemical etching and other etching techniques, metallization, and metal deposition.
The present inventive concept is a phase shifter which includes a basic electrostatically actuated cantilever switch spanning a slotline for use in reflecting electromagnetic energy. However, from a more basic perspective, the present invention is the utilization of a means for shorting a slotline to varying lengths of its initial predetermined length for phase shifting electromagnetic energy. This type of phase shifter is smaller, less expensive, lower loss, faster and requires less control power consumption than phase control elements used in the prior art. A series of these slotline arrangements create a phase shifter subarray which can be utilized for beam steering.